Multilayered photoresponsive device for electrophotography

ABSTRACT

This invention is directed to an improved photoresponsive device comprised of a substrate, a hole blocking layer, an optional adhesive layer, an inorganic photogenerating layer, an organic photoconductive layer sensitive to infra-red radiation, and a top coating of a hole transport layer. More specifically, the present invention is directed to an improved photoresponsive device comprised in the order stated of the following layers: (1) a conductive substrate, (2) a metal oxide hole blocking layer, (3) an adhesive layer, (4) an inorganic photogenerating layer, (5) a photoconductive composition capable of enhancing or reducing the intrinsic properties of the photogenerating layer, which composition is selected from the group consisting of organic photoconductive compositions, charge transfer complex compositions, sensitizers, or mixtures thereof, and (6) a hole transport layer.

BACKGROUND

This invention is generally directed to an improved overcoated layeredphotoresponsive device; and more specifically the present invention isdirected to an improved layered photoresponsive device where thesensitivity thereof can be varied or enhanced, allowing such a device tobe capable of being responsive to visible light, and infraredillumination needed for laser printing. In one important embodiment ofthe present invention, there is included in the device situated betweena photogenerating layer and a hole transport layer or situated between aphotogenerating layer, and a supporting substrate, a photoconductivecomposition, which composition is primarily responsible for enhancing orreducing the intrinsic properties of the photogenerating layer in theinfra-red and/or visible range of the spectrum, thereby allowing suchdevice to be sensitive to either visible light and/or infra-redwavelengths.

The formation and development of electrostatic latent images on theimaging surfaces of photoconductive materials by electrostatic means iswell known, one such method involving the formation of an electrostaticlatent image on the surface of a photosensitive plate, referred to inthe art as a photoreceptor. This photoreceptor is generally comprised ofa conductive substrate containing on its surface a layer ofphotoconductive material, and in many instances, a thin barrier layer issituated between the substrate and the photoconductive layer to preventcharge injection from the substrate, which injection would adverselyaffect the quality of the resulting image.

Numerous different xerographic photoconductive members are knownincluding, for example, a homogeneous layer of a single material such asvitreous selenium, or a composite layered device, containing adispersion of a photoconductive composition. An example of one type ofcomposite xerographic photoconductive member is described for example,in U.S. Pat. No. 3,121,006, wherein there is disclosed finely dividedparticles of a photoconductive inorganic compound dispersed in anelectrically insulating organic resin binder. In a commercial form, thebinder layer contains particles of zinc oxide uniformly dispersed in aresin binder, and coated on a paper backing. The binder materialsdisclosed in this patent comprise a material which is incapable oftransporting for any significant distance injected charge carriersgenerated by the photoconductive particles. Accordingly, as a result thephotoconductive particles must be in a substantially contiguous particleto particle contact throughout the layer for the purpose of permittingcharge dissipation required for a cyclic operation. Thus, with theuniform dispersion of photoconductive particles described a relativelyhigh volume concentration of photoconductor material, about 50 percentby volume, is usually necessary in order to obtain sufficientphotoconductor particle to particle contact for rapid discharge. Thishigh photoconductive loading can result in destroying the physicalcontinuity of the resin, thus significantly reducing the mechanicalproperties of the binder layer. Illustrative examples of specific bindermaterials disclosed in this patent include, for example, polycarbonateresins, polyester resins, polyamide resins, and the like.

There are also known photoreceptor materials comprised of otherinorganic or organic materials wherein the charge carrier generation andcharge carrier transport functions are accomplished by discretecontiguous layers. Additionally, layered photoreceptor materials aredisclosed in the prior art which include an overcoating layer of anelectrically insulating polymeric material. However, the art ofxerography continues to advance and more stringent demands need to bemet by the copying apparatus in order to increase performance standards,and to obtain higher quality images. Also, there is desired layeredphotoresponsive devices which are responsive to visible light andinfra-red illumination needed for laser printing.

Recently, there has been disclosed layered photoresponsive devicesincluding those comprised of generating layers and transport layers asdisclosed in U.S. Pat. No. 4,265,990, and overcoated photoresponsivematerials containing a hole injecting layer, overcoated with a transportlayer, followed by an overcoating of a photogenerating layer and a topcoating of an insulating organic resin, reference U.S. Pat. No.4,251,612. Examples of generating layers disclosed in these patentsinclude trigonal selenium, and phthalocyanines, and examples oftransport layers that may be employed are comprised of certain diaminesas mentioned herein. The disclosures of each of these patents, namely,U.S. Pat. Nos. 4,265,990 and 4,251,612 are totally incorporated hereinby reference.

Many other patents are in existence describing photoresponsive devicesincluding layered devices containing generating substances, such as U.S.Pat. No. 3,041,167, which discloses an overcoated imaging membercontaining a conductive substrate, a photoconductive layer, and anovercoating layer of an electrically insulating polymeric material. Thismember is utilized in an electrophotographic copying method by, forexample, initially charging the member, with an electrostatic charge ofa first polarity, and imagewise exposing to form an electrostatic latentimage, which can be subsequently developed to form a visible image.Prior to each succeeding imaging cycle, the imaging member can becharged with an electrostatic charge of a second polarity which isopposite in polarity to the first polarity. Sufficient additionalcharges of the second polarity are applied so as to create across themember a net electrical field of the second polarity. Simultaneously,mobile charges of the first polarity are created in the photoconductivelayer such as by applying an electrical potential to the conductivesubstrate. The imaging potential which is developed to form the visibleimage is present across the photoconductive layer and the overcoatinglayer.

There is also disclosed in Belgium Pat. No. 763,540, anelectrophotographic member having at least two electrically operativelayers, the first layer comprising a photoconductive layer which iscapable of photogenerating charge carriers, and injecting these carriersinto a continuous active layer containing an organic transportingmaterial which is substantially non-absorbing in the spectral region ofintended use, but which is active in that it allows injection ofphotogenerating holes from the photoconductive layer, and allows theseholes to be transported through the active layer. Additionally, there isdisclosed in U.S. Pat. No. 3,041,116 a photoconductive materialcontaining a transparent plastic material overcoated on a layer ofvitreous selenium contained on a substrate.

Further, there is disclosed in U.S. Pat. Nos. 4,232,102, and 4,233,383,photoresponsive imaging members comprised of trigonal selenium dopedwith sodium carbonate, sodium selenite mixtures, and barium carbonate,barium selenite mixtures.

Other representative patents disclosing layered photoresponsive devicesinclude U.S. Pat. Nos. 4,115,116, 4,047,949 and 4,081,274.

While the above-described photoresponsive devices are suitable for theirintended purposes there continues to be a need for the development ofimproved devices, particularly layered devices, which not only generateacceptable images, but which can be repeatedly used in a number ofimaging cycles without deterioration thereof from the machineenvironment or surrounding conditions. Additionally, there continues tobe a need for improved layered imaging members wherein the materialsselected for the respective layers are substantially inert to users ofsuch devices, while simultaneously functioning as an imaging member.Furthermore, there continues to be a need for imaging members whereinadhesion of the layers such as, for example, the photogenerating layerto the substrate can be accomplished without the need for specificadhesive materials, while simultaneously improving the scratchresistance of the other layers such as the ground plane layer, andimproving the strength of the binder generating layer. Also, therecontinues to be a need for overcoated photoresponsive devices which aresensitive to a broad range of wavelengths, and more specifically aresensitive to infra-red light, and visible light, thereby allowing suchdevices to be utilized in a number of imaging and printing systems.Further, there continues to be a need for improved photoresponsivedevices which can be prepared with a minimum number of processing steps,and wherein the layers are sufficiently adhered to one another to allowthe continuous use of such devices in repetitive imaging and printingsystems.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide animproved photoresponsive member which overcomes the above-noteddisadvantages.

It is yet another object of the present invention to provide an improvedlayered photoresponsive device which is panchromatic, and thus sensitiveto visible light as well as infra-red light.

A further specific object of the present invention is the provision ofan improved overcoated layered photoresponsive device containing aphotoconductive composition situated between a hole transport layer anda photogenerating layer.

It is yet another object of the present invention to provide an improvedlayered overcoated photoresponsive device containing a photoconductivecomposition situated between a photogenerating layer and a supportingsubstrate layer of such a device.

Another object of the present invention resides in the provision of animproved overcoated photoresponsive device containing a photoconductivecomposition situated between a hole transport layer and aphotogenerating layer, which device is simultaneously responsive toinfra-red light and visible light, and wherein the device has improvedadhesion properties.

In yet another object of the present invention there is provided imagingand printing methods utilizing the improved overcoated photoresponsivedevice of the present invention.

These and other objects of the present invention are accomplished by theprovision of an improved photoresponsive device comprising a layer of aphotoconductive composition situated between a photogenerating layer anda hole transport layer, or wherein the photoconductive composition layeris situated between the photogenerating layer and the supportingsubstrate of such a device. The improved photoresponsive device of thepresent invention thus contains a photoconductive composition layerwhich serves to enhance or reduce the intrinsic properties of thephotogenerating layer, in the infra-red and/or visible range of thespectrum.

In one specific embodiment, the present invention is directed to animproved photoresponsive device comprised in the order stated of (1) asubstrate, (2) a hole blocking layer, (3) an optional adhesive interfacelayer, (4) an inorganic photogenerating layer, (5) a photoconductivecomposition layer capable of enhancing or reducing the intrinsicproperties of the photogenerating layer, which composition is selectedfrom the group consisting of organic photoconductive materials, chargetransfer complex materials, and sensitizers, and (6) a hole transportlayer. In one important illustrative embodiment of the presentinvention, the photoresponsive device is comprised of a conductivesupporting substrate, a hole blocking metal oxide layer in contacttherewith, an adhesive layer, an inorganic photoconductivephotogenerating material overcoated on the adhesive layer, aphotoconductive composition capable of enhancing or reducing theintrinsic properties of the photogenerating layer in the infra-redand/or visible range of the spectrum, which composition is comprised ofa photoconductive material containing organic photoconductivesubstances, charge transfer complexes, sensitizers, or mixtures thereof,and as a top layer a hole transport layer comprised of certain diaminesdispersed in a resinous matrix. The photoconductive composition layer incontact with the hole transport layer must be capable of allowing holesgenerated by the photogenerating layer to be transported, and also thislayer should not trap the generated holes. Further, the photoconductivecomposition layer should be comprised of materials that havetransmissive properties, that is materials that allow the passage of thelight required to produce electron hole pairs in the photogeneratinglayer. Also, the photoconductive layer can function as a selectivefilter, allowing light of a certain wavelength to penetrate to thephotogenerating layer.

In another important embodiment, the present invention is directed to animproved photoresponsive device as described hereinbefore, with theexception that the photoconductive composition capable of enhancing orreducing the intrinsic properties of the photogenerating layer issituated between the photogenerating layer, and the supporting substratecontained in the device. Accordingly, in this variation, thephotoresponsive device of the present invention comprises in the orderstated (1) a substrate, (2) a hole blocking layer, (3) an optionaladhesive, or adhesion interface layer, (4) a photoconductive compositionlayer capable of enhancing or reducing the intrinsic properties of thephotogenerating layer in the infra-red and/or visible range of thespectrum, which composition is comprised of organic photoconductivematerials, charge transfer complex materials, sensitizers, or mixturesthereof, (5) an inorganic photogenerating layer, and (6) a holetransport layer.

Exposure to illumination and erasure, of the layered photoresponsivedevices of the present invention may be accomplished from the frontside,from the rearside, or combinations thereof.

The improved photoresponsive devices of the present invention can beprepared by a number of known methods, the process parameters and theorder of the coating of the layers being dependent on the devicedesired. Thus, for example, the improved photoresponsive device of thepresent invention can be prepared by providing a conductive substratecontaining a hole blocking layer, and an optional adhesive layer, andapplying thereto by solvent coating processes, laminating processes, orother methods, a photogenerating layer, an organic photoconductivecomposition capable of enhancing or reducing the intrinsic properties ofthe photogenerating layer in the infra-red and/or visible range of thespectrum, and a hole transport layer.

The improved photoresponsive device of the present invention can beincorporated in various imaging systems and more importantly canfunction simultaneously in imaging and printing systems with visiblelight and/or infra-red light. Thus, the improved photoresponsive deviceof the present invention may be negatively charged, exposed to light ina wavelength range of from about 400 to about 1,000 nanometers, eithersequentially or simultaneously, followed by developing the resultantimage, and transferring to paper. The above sequence may be repeatedmany times.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention and further featuresthereof, reference is made to the following detailed description ofvarious preferred embodiments wherein:

FIGS. 1 and 2 are partially schematic cross-sectional views of theimproved photoresponsive device of the present invention;

FIG. 3 is a partially schematic cross-sectional view of a preferredphotoresponsive device of a present invention;

FIG. 4 illustrates a further preferred embodiment of the photoresponsivedevice of the present invention;

FIG. 5 illustrates another preferred embodiment of the photoresponsivedevice of the present invention;

FIG. 6 illustrates another preferred embodiment of the photoresponsivedevice of the present invention;

FIGS. 7, 8 and 9 are spectral response curves wherein there is plottedfor various photoresponsive devices, photosensitivity as a function ofwavelength;

FIG. 7 illustrates the percent discharge for the photoresponsive deviceof Example V for 5 ergs cm⁻² exposure from a dark development potential(V_(DDP)) of -800 volts as a function of light exposure in thewavelength of 400 nanometers to 1,000 nanometers. This device has noinfra-red sensitivity.

FIG. 8 illustrates the percent discharge for the photoresponsive deviceof Example VI for 5 ergs cm⁻² exposure from a dark development potential(V_(DDP)) of -800 volts as a function of light exposure in thewavelength of from about 400 nanometers to about 1,000 nanometers. Thisfigure demonstrates that such a device possesses red and infra-redsensitivity, but lacks good blue and green sensitivity.

FIG. 9 represents the percent discharge for the photoresponsive deviceof the present invention, reference Example X, for 5 ergs cm⁻² exposureof this device from a dark development potential (V_(DDP)) of -800 voltsas a function of light exposed in the wavelength of 400 to 1,000nanometers. This figure demonstrates the visible and infra-redsensitivity of the devices of the present invention.

The percent discharge referenced in the Figures is defined as ##EQU1##wherein V_(DDP) is the dark development potential, and V (volts) 5 ergscm⁻² is the surface potential in volts on the photoreceptor afterexposure to 5 ergs cm⁻² of light in the wavelength range 400 to 1,000nanometers.

As an example, for a V_(DDP) of -800 volts and a surface potential of400 volts, after 5 ergs cm⁻² exposure at, for example 800 nanometers,the percent discharge of the device involved would be 50 percent.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Illustrated in FIG. 1 is the improved photoresponsive device of thepresent invention, generally designated 10, and comprising a substrate3, a hole blocking metal oxide layer 5, an optional adhesive layer 6, acharge carrier inorganic photogenerating layer 7, an organicphotoconductive composition layer 9 capable of enhancing or reducing theintrinsic properties of the photogenerating layer 7 in the infra-redand/or visible range of the spectrum, and a charge carrier, or holetransport layer 11.

Illustrated in FIG. 2 is essentially the same device as illustrated inFIG. 1 with the exception that the photoconductive layer 9 is situatedbetween the inorganic photogenerating layer 7 and the substrate 3, andmore specifically, the photoconductive layer 9 in this embodiment isspecifically situated between the optional adhesive layer 6 and thecharge carrier inorganic photogenerating layer 7.

The substrate layer 3 may be opaque or substantially transparent, andmay comprise any suitable material having the requisite mechanicalproperties. Thus the substrate may comprise a layer of insulatingmaterial such as an inorganic or organic polymeric material; a layer ofan organic or inorganic material having a semi-conductive surface layersuch as indium tin oxide, arranged thereon, or a conductive materialsuch as, for example, aluminum, chromium, nickel, brass or the like. Thesubstrate may be flexible or rigid and many have a number of manydifferent configurations, such as, for example, a plate, a cylindricaldrum, a scroll, an endless flexible belt and the like. Preferably, thesubstrate is in the form of an endless flexible belt. In somesituations, it may be desirable to coat on the back of the substrate,particularly when the substrate is an organic polymeric material, ananti-curl layer, such as for example, polycarbonate materialscommercially available as Makrolon.

The thickness of the substrate layer depends on many factors, includingeconomical considerations, and this layer may be of substantialthickness, for example, over 100 mils, or of minimum thickness,providing there are no adverse effects on the system. In one preferredembodiment the thickness of this layer ranges from about 3 mils to about10 mils.

The hole blocking metal oxide layer 5 can be comprised of varioussuitable known materials including aluminum oxide, and the like. Thepreferred metal oxide layer is aluminum oxide. The primary purpose ofthis layer is to provide hole blocking, that is to prevent holeinjection from the substrate during and after charging. Typically, thislayer is of a thickness of less than 50 Angstroms.

Adhesive layer 6, is typically a polymeric material, includingpolyesters, polyvinyl butyral, polyvinyl pyrrolidone and the like.Typically, this layer is of a thickness of less than about 0.3 microns.

The inorganic photogenerating layer 7 can be comprised of knownphotoconductive charge carrier generating materials sensitive to visiblelight, such as amorphous selenium, amorphous selenium alloys, halogendoped amorphous selenium, halogen doped amorphous selenium alloys,trigonal selenium, mixtures of Groups IA and IIA element, selenite andcarbonates with trigonal selenium, reference U.S. Pat. Nos. 4,232,102and 4,233,283, cadmium sulphide, cadmium selenide, cadmium telluride,cadmium sulfur selenide, cadmium sulfur telluride, cadmium selenotelluride, copper, and chlorine doped cadmium sulphide, cadmium selenideand cadmium sulphur selenide and the like. Alloys of selenium includedwithin the scope of the present invention include selenium telluriumalloys, selenium arsenic alloys, selenium tellurium arsenic alloys, andpreferably such alloys containing a halogen material such as chlorine inan amount of from about 50 to about 200 parts per million.

Layer 7 typically has a thickness of from about 0.05 microns to about 10microns or more, and preferably from about 0.4 microns to about 3microns, however, the thickness of this layer is primarily dependent onthe photoconductive volume loading, which may vary from 5 to 100 volumepercent. Generally, it is desirable to provide this layer in a thicknesswhich is sufficient to absorb about 90 percent or more of the incidentradiation which is directed upon it in the imagewise or printingexposure step. The maximum thickness of this layer is dependentprimarily upon factors such as mechanical considerations, for examplewhether a flexible photoresponsive device is desired.

A very important layer of the photoresponsive device of the presentinvention is the photoconductive layer 9 which can be comprised ofnumerous organic photoconductive substances, charge transfer complexes,squarylium pigments, various sensitizers, mixtures thereof and the like.Illustrative examples of materials useful in this layer include metalphthalocyanines, metal free phthalocyanines, vanadyl phthalocyanines,other known phthalocyanines, as disclosed in U.S. Pat. No. 3,816,118,the disclosure of which is totally incorporated herein by reference,squarylium pigments, charge transfer complex materials such as polyvinylcarbazole-trinitrofluoronone, particularly polyvinyl carbazole2,4,7-trinitrofluoronone, and various infra-red sensitizers, such ascyanine dyes, described in the Chemistry of Synethtic Dyes, Volume IIand Volume IV, 1971, Academic Press, edited by K. Venkataraman.

Specific illustrative examples of squarylium pigments that can beselected for layer 9 include, for example, those of the followingformula: ##STR1## wherein R is hydrogen, an alkyl group such as methyl,or a hydroxy (OH) group.

The materials selected for layer 9, reference FIG. 1, must beelectronically compatible with the charge carrier transport layer 11, inorder that photoexcited charge carriers can be injected into thetransport layer, and further, in order that charge carriers can travelin both directions across the interface between the photoconductivelayer 9, and the charge transport layer 11. One preferred material forlayer 9 that accomplishes these functions is vanadyl phthalocyanine,primarily since it is readily available, and provides the desired levelof enhancement of the intrinsic properties of the photogenerating layer,in the infra-red range of the spectrum, about 700 nanometers to about920 nanometers.

The inorganic photogenerating materials for layer 7, or thephotoconductive materials for layer 9, can comprise 100 percent of therespective layers, or these materials can be dispersed in varioussuitable inorganic or resinous polymer binder materials, in amounts offrom about 5 percent by volume to about 95 percent by volume, andpreferably in amounts of from about 25 percent by volume to about 75percent by volume. Illustrative examples of polymeric binder resinousmaterials that can be selected include those as disclosed, for example,in U.S. Pat. No. 3,121,006, the disclosure of which is totallyincorporated herein by reference, polyesters, polyvinyl butyral,Formvar®, polycarbonate resins, polyvinyl carbazole, epoxy resins,phenoxy resins, especially the commercially available poly(hydroxyether)resins.

In one embodiment of the present invention, the charge carrier transportmaterial, such as the diamine described hereinafter, may be incorporatedinto layer 7, and/or layer 9, in amounts for example, ranging from aboutzero volume percent to 60 volume percent.

Generally, the thickness of layer 9 depends on a number of factorsincluding the thicknesses of the other layers, and the percent mixtureor photoconductive material contained in this layer. Accordingly, thislayer can range in thickness of from about 0.05 microns to about 10microns when a photoconductive composition such as vanadylphthalocyanine is present in an amount of from about 5 percent to about100 percent by volume, and preferably this layer ranges in thickness offrom about 0.25 microns to about 1 micron, when the photoconductivecomposition such as vanadyl phthalocyanine is present in this layer inan amount of 30 percent by volume. The maximum thickness of this layeris dependent primarily upon factors such as mechanical considerations,for example whether a flexible photoresponsive device is desired.

Charge carrier transport layer 11 can be comprised of a number ofnumerous suitable materials which are capable of transporting holes,this layer generally having a thickness in the range of from about 5microns to about 50 microns, and preferably from about 20 microns toabout 40 microns. In a preferred embodiment, this transport layercomprises molecules of the formula: ##STR2## dispersed in a highlyinsulating and transparent organic resinous binder wherein X is selectedfrom the group consisting of (ortho) CH₃, (meta) CH₃, (para) CH₃,(ortho) Cl, (meta) Cl, (para) Cl. The highly insulating resin, which hasa resistivity of at least 10¹² ohm-cm to prevent undue dark decay, is amaterial which is not necessarily capable of supporting the injection ofholes from the photogenerating layer, and is not capable of allowing thetransport of these holes through the material. However, the resinbecomes electrically active when it contains from about 10 to 75 weightpercent of the substitutedN,N,N',N'-tetraphenyl[1,1-biphenyl]4-4'-diamines corresponding to theforegoing formula.

Compounds corresponding to the above formula include, for example,N,N'-diphenyl-N,N'-bis(alkylphenyl)-[1,1-biphenyl]-4,4'-diamine whereinthe alkyl is selected from the group consisting of methyl such as2-methyl, 3-methyl and 4-methyl, ethyl, propyl, buyl, hexyl and thelike. In the case of chloro substitution, the compound is namedN,N'-diphenyl-N,N'-bis(halo phenyl)-[1,1'-biphenyl]-4,4'-diamine whereinthe halo atom is 2-chloro, 3-chloro or 4-chloro.

Other electrically active small molecules which can be dispersed in theelectrically inactive resin to form a layer which will transport holesinclude, bis(4-diethylamine-2-methylphenyl)phenylmethane;4',4"-bis(diethylamino)-2'2"-dimethyltriphenyl methane;bis-4(diethylaminophenyl)phenylmethane; and4,4'-bis(diethylamino)-2,2'-dimethyl triphenylmethane.

Providing the objectives of the present invention are achieved, othercharge carrier transport molecules can be selected for layer 11.

Examples of the highly insulating and transparent resinous material orinactive binder resinous material, for layer 11, include materials suchas those described in U.S. Pat. No. 3,121,006 the disclosure of which istotally incorporated herein by reference. Specific examples of organicresinous materials include polycarbonates, acrylate polymers, vinylpolymers, cellulose polymers, polyesters, polysiloxanes, polyamides,polyurethanes and epoxies as well as block, random or alternatingcopolymers thereof. Preferred electrically inactive binder materials arepolycarbonate resins having a molecular weight (M_(w)) of from about20,000 to about 100,000 with a molecular weight in the range of fromabout 50,000 to about 100,000 being particularly preferred. Generally,the resinous binder contains from about 10 to about 75 percent by weightof the active material corresponding to the foregoing formula, andpreferably from about 35 percent to about 50 percent of this material.

Illustrated in FIG. 3 is one preferred photoresponsive device of thepresent invention wherein the substrate 15 is comprised of Mylar in athickness of 3 mils, containing a layer of 20 percent transmissivealuminum in a thickness of about 100 Angstroms, the metal oxide layer 17is comprised of aluminum oxide in a thickness of about 20 Angstroms,layer 18 is a polyester adhesive interface commercially available fromE. I. duPont, as 49,000 polyester in a thickness of about 0.05 microns,the inorganic photogenerating layer 19 is of a thickness of about 2.0microns and is comprised of 10 volume percent Na₂ SeO₃ and Na₂ CO₃ dopedtrigonal selenium in a polyvinyl carbazole binder, the photoconductivelayer 21 has a thickness of about 0.5 microns, and is comprised of 30volume percent vanadyl phthalocyanine dispersed in a polyester binder,70 volume percent, and the hole transport layer 23, thickness about 25microns is comprised of 50 weight percentN,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1' -biphenyl]-4,4'-diamine,dispersed in a polycarbonate resinous binder.

Illustrated in FIG. 4 is another preferred photoresponsive device of thepresent invention, wherein layers 25, 27, 28, 29 and 33 are identical tolayers 15, 17, 18, 19 and 23, as described with reference to FIG. 3. InFIG. 4, the photoconductive layer 31, rather than being vanadylphthalocyanine, is comprised of about 30 volume percent of hydroxysquarylium dispersed in a resinous binder material, 70 volume percentcommercially available as Formvar® from Monsanto Chemical Company.

There is illustrated in FIG. 5 a further embodiment of thephotoresponsive device of the present invention, wherein the substrate35, is comprised of Mylar in a thickness of 3 mils, containing about a100 Angstrom layer of 20 percent transmissive aluminum, the metal oxidehole blocking layer 37 is aluminum oxide in a thickness of about 20Angstroms, the optional adhesive layer 38 is a polyester materialcommercially available from E. I. duPont Company, as duPont 49,000, thislayer having a thickness of about 0.05 microns, the photogeneratinglayer 39 is comprised of 33 percent by volume of trigonal seleniumdispersed in a phenoxy resinous binder, commercially available as thepoly(hydroxyether) Bakelite from Allied Chemical Corporation, this layerhaving a thickness of 0.4 microns, a photoconductive layer 41, comprisedof 30 percent by volume of vanadyl phthalocyanine dispersed in apolyester binder, which layer has a thickness of about 0.5 microns, anda hole transport layer 43, in a thickness of 25 microns, comprised of 50percent by weight ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine,dispersed in a polycarbonate resinous binder.

Illustrated in FIG. 6 is a further preferred photoresponsive device ofthe present invention, wherein the layers 47, 49, 51, 53 and 57, areidentical to the layers 35, 37, 38, 39 and 43, which reference to FIG.5. In FIG. 6 the photoconductive layer 55 is comprised of 30 volumepercent of hydroxy squarylium dispersed in the resinous binder Formvar®.

As indicated herein, illustrated in FIGS. 7, 8, and 9, are spectralresponse graphs or curves wherein the photosensitivity of variousphotoresponsive devices are plotted as a function of wavelength.

Illustrated in FIG. 7 is a photoresponsive device prepared in accordancewith Example V, and containing a Mylar substrate, 3 mils in thickness, alayer of 20 percent transmissive aluminum, about 100 Angstrom units inthickness, a hole blocking layer of aluminum oxide of about 20 Angstromunits in thickness, an adhesive layer of a polyester material,commercially available from E. I. duPont as duPont 49,000, of athickness of about 0.05 microns, and a generating layer, 0.4 micronsthick, containing 33 percent by volume of trigonal selenium dispersed inphenoxy resinous binder, commercially available as a poly(hydroxyether)from Allied Chemical Company, and a transport layer, 25 microns inthickness comprised of 50 weight percent ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diaminedispersed in a polycarbonate resinous binder, which device hasessentially no infra-red sensitivity in that at a wavelength of about700 nanometers, the percent discharge of this device is substantiallyzero.

Illustrated in FIG. 8 is a photoresponsive device prepared in accordancewith Example VI, and containing a Mylar substrate, in a thickness of 3mils, a layer of 20 percent transmissive aluminum, in a thickness ofabout 100 Angstrom units, a hole blocking layer of aluminum oxide, in athickness of about 20 Angstrom units, an adhesive layer of a polyestermaterial, commercially available as duPont 49,000, in a thickness ofabout 0.05 microns, overcoated with a photogenerating layer of vanadylphthalocyanine, 30 percent by volume dispersed in a polyester resinousbinder, about 0.5 microns in thickness, which in turn is overcoated witha transport layer, 25 microns in thickness comprised of 50 percent byweight ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diaminedispersed in a polycarbonate resinous binder, which device had poorvisible blue and green sensitivity as evidenced by a dischargepercentage of less than 30 at wavelengths of less than 550 nanometers,for example.

Illustrated in FIG. 9 is a photoresponsive device of the presentinvention as prepared in accordance with Example X, and containing thesubtrate, 3 mils in thickness, a layer of 20 percent transmissivealuminum, about 100 Angstrom units in thickness, a hole blocking layerof aluminum oxide, in a thickness of about 20 Angstrom units, anadhesive layer of a polyester, commercially available as duPont 49,000,in a thickness of about 0.05 microns, a generating layer, 0.4 micronsthick, containing 33 percent by volume of trigonal selenium, dispersedin a phenoxy resinous binder, commercially available as apoly(hydroxyether) Bakelite from Allied Chemical Corporation, overcoatedwith a photoconductive layer of vanadyl phthalocyanine, 30 percent byvolume dispersed in a polyester resinous binder, about 0.5 microns inthickness or overcoated with a photoconductive layer of vanadylphthalocyanine 30 percent by volume, dispersed in a polyester resinousbinder, about 1.0 microns in thickness, and a transport layer, 25microns in thickness comprised of 50 percent by weight ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diaminedispersed in a polycarbonate resinous binder. This device hassensitivity both in the visible range of the spectrum, a wavelength offrom about 400 nanometers to about 700 nanometers, as well assensitivity in the infra-red region, that is from about 700 to about 950nanometers.

The invention will now be described in detail with respect to specificpreferred embodiments thereof, it being understood that these examplesare intended to be illustrative only, and the invention is not intendedto be limited to the materials, conditions, or process parameters,recited herein. All parts and percentages are by weight unless otherwiseindicated.

EXAMPLE I Preparation ofN,N-diphenyl-N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4,4'-diamine

In a 5,000 milliliter (ml), round bottom 3, necked flask fitted with amechanical stirrer and blanketed with argon, is placed 336 grams (1mole) of N,N'-diphenyl[1,1'-biphenyl]-4,4'-diamine, 550 grams (2.5moles) of m-iodotoluene, 550 grams (4 moles) potassium carbonate(anhydrous), 50 grams of a copper bronze catalyst, and 1,500 mldimethylsulfoxide (anhydrous). The heterogeneous mixture is refluxed for6 days. The mixture is allowed to cool, and 200 ml of benzene is added.The dark slurry is then filtered. The filtrate is extracted 4 times withwater. Then the filtrate is dried with magnesium sulfate and filtered.The benzene is taken off under reduced pressure. The black product iscolumn chromatographed using Woelm neutral alumina. Colorless crystalsof the above diame product are obtained by recrystallizing the productfrom n-octane. The melting point is 167. 169° C. The yield is 360 grams(65 percent).

Analytical Calculation for C₃₈ H₃₂ N₂ : C, 88.34; H, 6.24; N, 5.37.Found: C, 88.58; H, 6.21; N, 5:37.

EXAMPLE II Preparation ofN,N-diphenyl-N,N'-bis(4-methylphenyl)-[1,1'-biphenyl]4,4'-diamine

In a 500 milliliter, round bottom flask, equipped with a magneticstirrer and purged with argon, is charged with 20 grams ofp,p-diiodobiphenyl (0.05 mole), 18.3 grams of p-tolylphenyl-amine (0.1mole), 20.7 grams potassium carbonate (anhydrous) (0.15 mole), 3.0 gramsof copper powder and 50 mils of sulfolane(tetrahydrothiophene-1,1-dioxide). The mixture is heated to 220°-225° C.for 24 hours, allowed to cool to approximately 150° C. and 300milliliters of deionized water are added. The heterogeneous mixture isheated to reflux while vigorously stirring. A light tan oily precipitateis formed in the flask. The water is then decanted. Then 300 millilitersof water are added, and the water layer was again decanted. 300milliliters of methanol was added and the mixture was refluxed todissolve any unreacted starting materials. The solids were filtered off,added to 300 milliliters of n-octane and heated to a reflux temperatureof 125° C. The solution was filtered through 100 grams of neutral Woelmalumina to give a pale yellow filtrate. The solution was again filteredthrough 100 grams of neutral Woelm alumina to yield a colorless filtrateand was allowed to cool yielding colorless crystals of the intendedcompound having a M.P. of 163°-165° C.

Analytical Calculation for C₃₈ H₃₂ N₂ : C, 88.34; H, 6.24; N, 5.37.Found: C, 88.49; H, 6.44; N, 5:28.

EXAMPLE III

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto, wet thickness,0.5 mils, a layer of 0.5 weight percent duPont 49,000 adhesive, apolyester available from E. I. duPont, in methylene chloride and1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator. Thislayer was allowed to dry for one minute at room temperature, and 10minutes at 100° C. in a forced air oven, resulting in a layer having adry thickness of about 0.05 microns.

There was then overcoated on the adhesive layer 10 volume percent of aphotogenerating layer comprised of trigonal selenium prepared asfollows:

In a 2 oz. amber bottle there was added 0.8 grams polyvinyl carbazoleand 14 milliliters, 1:1 volume ratio, tetrahydrofuran and toluene. Therewas then added to this solution 0.8 grams of trigonal selenium, and 100grams of stainless steel shot, 3/8" in diameter. The above mixture wasthen placed on a ball mill for 72 to 96 hours. Subsequently, 5 grams ofthe resulting slurry were added to a solution of 0.18 grams of polyvinylcarbazole, and 0.15 grams ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine, in 6.3milliliters of tetrahydrofuran-toluene, volume ratio 1:1. This slurrywas then placed on a shaker for 10 minutes. The resulting slurry wasthen coated on the above adhesive interface with a Bird applicator, wetthickness 0.5 mils. This layer was then dried at 130° C. for 6 minutesin a forced air oven, resulting in a dry thickness of 2.0 microns. Theresulting layer contained 10 volume percent of trigonal selenium and 25volume percent of the diamine, and 65 volume percent of polyvinylcarbazole.

The above photogenerator layer was overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight of Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000, commercially available from LarbensabrickenBayer A.G., was mixed with 50 percent by weight ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Theresulting solution was then mixed in 15 percent by weight of methylenechloride. All of the above components were then placed into an amberbottle and dissolved. The mixture was coated to a dry 25 micronthickness layer on top of the photogenerator layer using a Birdapplicator. During this coating process the humidity was equal to orless than 15 percent. The resulting device containing all of the abovelayers was annealed at 135° C. in a forced air oven for 6 minutes.

EXAMPLE IV

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 weight percent of duPont 49,000adhesive, a polyester available from E. I. duPont, in methylene chlorideand 1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator.This layer was then allowed to dry for one minute at room temperatureand 10 minutes at 100° C. in a forced air oven. The resulting layer hada dry thickness of 0.05 microns.

There was then overcoated on the above adhesive layer, a photogeneratinglayer containing 30 volume percent of a trigonal selenium, 25 volumepercent N,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamineand 45 volume percent of polyvinyl carbazole prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole, and 18milliliters, 1:1 by volume, tetrahydrofuran/toluene. Added to thissolution was 2.1 grams of trigonal selenium, and 100 grams of stainlesssteel shot, 1/8" in diameter. The above mixture was then placed on aball mill for 72 to 96 hours, resulting in a slurry. In a 1 oz. amberbottle was added 0.04 gramsN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine, and6.4 milliliters of tetrahydrofuran/toluene. Added to this solution was 2grams of the ball milled slurry. The resulting mixture was then placedon a shaker for 10 minutes, and the slurry formed was then coated on theabove 49,000 adhesive layer with a Bird applicator, at a wet thickness0.5 mils. This device was then dried at 135° C. for 6 minutes in aforced air oven. The dry thickness of the photogenerating generatorlayer was 0.5 microns.

The above photogenerator layer was then overcoated with a chargetransport layer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weight ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Theresulting was then mixed in 15 percent by weight methylene chloride. Allof the above components were then placed into an amber bottle anddissolved. The mixture was then coated to a dry 25 micron thicknesslayer on top of the photogenerator layer using a Bird applicator. Duringthis coating process, the humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE V

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent by weight of duPont 49,000adhesive, a polyester available from duPont, in methylene chloride and1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator. The wetthickness was 0.5 mil. This layer was then allowed to dry for one minuteat room temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of about 0.05 microns.

A photogenerator layer containing 33 percent by volume of trigonalselenium, and 13 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diaminedispersed in 54 percent of the phenoxy resinous binder available fromUnion Carbide as Bakelite PHKK was prepared as follows:

In a 4 oz. amber bottle was added 1.6 grams of the above phenoxy resinand 0.4 gramsN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine, in 21milliliters of methyl ethyl ketone and 7 milliliters methoxyethylacetate (cellosolve acetate). Added to this solution was 3.2 grams oftrigonal selenium, and 200 grams of stainless steel shot, 1/8" indiameter. The above mixture was then placed on a ball mill for 72 to 96hours. The slurry was then coated on the above duPont 49,000 adhesivelayer with a Bird applicator, in a wet thickness 0.5 mils. This devicewas then dried at 135° C. for 6 minutes in a forced air oven. The drythickness of the photogenerating generator layer was 0.5 microns.

The above photogenerator layer was then overcoated with a chargetransport layer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Theresulting solution was then mixed in 15 percent by weight of methylenechloride. All of the above components were then placed into an amberbottle and dissolved. The mixture was coated to a dry 25 micronthickness layer on top of the generator layer using a Bird applicator.During the coating process the humidity was equal to or less than 15percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE VI

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto a layer of 0.5percent by weight of duPont 49,000 adhesive, in methylene chloride and1,1,2-trichloroethane 4:1 volume with a Bird Applicator. The layer wasallowed to dry for one minute at room temperature, and 10 minutes at100° C. in a forced air oven. The dry thickness of the resulting layerwas 0.05 microns.

A photoconductive layer containing 30 percent by volume of vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000 polyesterin 16 milliliters methylene chloride. Added to this solution was 0.36grams of vanadyl phthalocyanine, and 100 grams 1/8" stainless steelshot. The above mixture was placed on a ball mill for 24 hours. To 5grams of this slurry was added 10 milliliters of methylene chloride.This slurry is coated on the above polyester adhesive layer with a Birdapplicator, to a wet thickness of 0.5 mils. This layer was allowed toair dry for 5 minutes. This device was dried at 135° C. for 6 minutes ina forced air oven. The dry thickness was 0.5 microns.

The above photoconductive layer was then overcoated with a chargetransport layer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabriken Bayer A.G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was then mixed in 15 percent by weight of methylene chloride.All of these components were placed into an amber bottle and dissolved.The mixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processhumidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE VII

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent weight of duPont 49,000polyester adhesive, in methylene chloride and 1,1,2-trichloroethane (4:1volume ratio) with a Bird Applicator. The layer was allowed to dry forone minute at room temperature, and 10 minutes at 100° C. in a forcedair oven. The resulting layer had a dry thickness of 0.5 microns.

A photoconductive layer containing 30 percent by volume of hydroxysquarylium was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams Formuar 12.85, commerciallyavailable from Monsanto Chemical Company and 16 milliliters oftetrahydrofuran. Added to this solution was 0.36 grams of hydroxysquarylium, and 100 grams 1/8" stainless steel shot. The above mixturewas placed on a ball mill for 24 hours. To 5 grams of this slurry wasadded 10 milliliters of tetrahydrofuran. This slurry was then coated onthe above adhesive layer with a Bird applicator, to a wet thickness of0.5 mils. The resulting layer was allowed to air dry for 5 minutes. Thisdevice was dried at 135° C. for 6 minutes in a forced air oven. The drythickness of the photoconductive layer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A.G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processhumidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE VIII

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent weight of duPont 49,000adhesive, in methylene chloride and 1,1,2-trichloroethane 4:1 volumewith a Bird Applicator. The layer was allowed to dry for one minute atroom temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of 0.05 microns.

A photogenerator layer containing 10 volume percent of trigonalselenium, 25 percent by volumeN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine and 65volume percent of polyvinyl carbazole was then prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole and 14milliliters 1:1 by volume tetrahydrofuran/toluene. Added to thissolution was 0.8 grams of trigonal selenium and 100 grams of 1/8"stainless steel shot. The above mixture was placed on a ball mill for72-96 hours. Five grams of this slurry was added to a solution of 0.18grams of polyvinyl carbazole and 0.15 gramsN,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine in 6.3 milliliters oftetrahydrofuran/toluene. This mixture was placed on a shaker for 10minutes. The slurry was then coated on the above adhesive interface witha Bird applicator. The wet thickness was 0.5 mils. This layer was driedat 135° C. for 6 minutes in a forced air oven. The dry thickness was 2.0microns.

A photoconductive layer containing 30 percent by volume vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000 in 16milliliters methylene chloride. Added to this solution was 0.36 grams ofvanadyl phthalocyanine and 100 grams 1/8" stainless steel shot. Theabove mixture was placed on a ball mill for 24 hours. To 5 grams of thisslurry was added 10 milliliters of methylene chloride. This slurry wasthen coated on the above photogenerator layer with a Bird applicator toa wet thickness of 0.5 mil. This layer was allowed to air dry 1-5minutes to a dry thickness of 0.5 microns. The resulting device wasdried at 135° C. for 6 minutes in a forced air oven.

The above photoconductive layer was overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was thenannealed at 135° C. in a forced air oven for 6 minutes.

EXAMPLE IX

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils a layer of 0.5 percent weight of duPont 49,000polyester adhesive, in methylene chloride and 1,1,2-trichloroethane (4:1volume ratio) with a Bird Applicator. The layer was allowed to dry forone minute at room temperature, and 10 minutes at 100° C. in a forcedair oven.

A photogenerator layer containing 30 percent by volume of trigonalselenium and 25 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine wasthen prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole, and 18milliliters, 1:1 by volume, tetrahydrofuran/toluene. Added to thissolution was 2.1 grams of trigonal selenium, and 100 grams of stainlesssteel shot, 1/8" in diameter. The above mixture was then placed on aball mill for 72 to 96 hours. In a 1 oz. amber bottle was added 0.04grams ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine, and6.4 milliliters of tetrahydrofuran/toluene. Added to this solution was 2grams of the ball milled slurry. The resulting mixture was placed on ashaker for 10 minutes, and the slurry formed was then coated on theabove 49,000 adhesive layer with a Bird applicator, in a wet thickness0.5 mils. This device was allowed to air dry for 5 minutes. The drythickness of the resulting photogenerating generator layer was 0.5microns. This layer was dried at 135° C. for 6 minutes.

A photoconductive layer containing 30 percent by volume of vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000 polyesterin 16 milliliters of methylene chloride. Added to this solution was 0.36grams of vanadyl phthalocyanine, and 100 grams of 1/8" stainless steelshot. The above mixture was the placed on a ball mill for 24 hours. To 5grams of the resulting slurry there was added 10 milliliters ofmethylene chloride. The slurry was then coated on the abovephotogenerating layer with a Bird applicator, to a wet thickness of 0.5mils. The layer was then allowed to air dry for 5 minutes to a drythickness of 0.5 microns. The resulting layer was then dried at 135° C.for 6 minutes in a forced air oven.

The above photoconductive layer was overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A.G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were then placed into an amber bottle and dissolved.The mixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was thenannealed at 135° C. in a forced air oven for 6 minutes.

EXAMPLE X

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 weight percent DuPont 49,000adhesive, in methylene chloride and 1,1,2-trichlorethane (4:1 volumeratio) with a Bird Applicator. This layer was then allowed to dry forone minute at room temperature, and 10 minutes at 100° C. in a forcedair oven. The resulting layer had a dry thickness of 0.05 microns.

A photogenerator layer was then prepared containing 33 percent by volumeof trigonal selenium, and 13 percent by volumeN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diaminedispersed in a phenoxy resinous binder 54, percent by volume, wasprepared as follows:

In a 4 oz. amber bottle was added 1.6 grams of the phenoxy resinBakelite, available from Union Carbide, 21 milliliters of methyl ethylketone, and 7 milliliters of methoxy ethyl acetate. Added to thissolution was 3.2 grams of trigonal selenium, and 200 grams 1/8"stainless steel shot. The above mixture was placed on a ball mill for72-96 hours. The slurry formed was then coated on the above interfacewith a Bird applicator, to a wet thickness of 0.5 mil and, the resultinglayer was allowed to air dry for 5 minutes to a dry thickness of 0.5microns. The layer was then dried at 135° C. for 6 minutes in a forcedair oven.

A photoconductive layer containing 30 percent by volume of vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000 polyesteradhesive, and 16 ml of methylene chloride. Added to this solution was0.36 grams of vanadyl phthalocyanine and 100 grams 1/8" stainless steelshot. The above mixture was placed on a ball mill for 24 hours. To 5grams of this slurry was added 10 milliliters of methylene chloride.This slurry was coated on the above photogenerator layer with a Birdapplicator to a wet thickness of 0.5 mils. This layer was allowd to airdry for 5 minutes. The device was dried at 135° C. for 6 minutes in aforced air oven, to a dry thickness of 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. Humidity was equal to or lessthan 15 percent.

The resulting device containing all of the above layers was thenannealed at 135° C. in a forced air oven for 6 minutes.

A photoresponsive device was prepared by repeating the above processwith the exception that the photoconductive layer thickness was 1.0microns.

EXAMPLE XI

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils and applying thereto a layer of 0.5percent by weight duPont 49,000 adhesive, a polyester available fromduPont, in methylene chloride, and 1,1,2-trichloroethane (4:1 volumeratio) with a Bird applicator, to a wet thickness of 0.5 mils. The layerwas allowed to dry for one minute at room temperature, and 10 minutes at100° C. in a forced air oven. The resulting layer had a dry thickness ofabout 0.05 microns.

A photogenerator layer containing 10 percent volume trigonal selenium,and 25 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-bisphenyl-4,4'-diamine and 65volume percent of polyvinyl carbazole was then prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole and 14milliliters; 1:1 volume ratio, tetrahydrofuran:toluene. There was thenadded to this solution 0.8 grams of trigonal selenium and 100 grams ofstainless steel shot, 1/8" in diameter. The above mixture was thenplaced on a ball mill for 72 to 96 hours. Subsequently, 5 grams of theresulting slurry were added to a solution of 0.18 grams of polyvinylcarbazole, and 0.15 grams ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine, in 6.3milliliters of tetrahydrofuran-toluene, volume ratio 1:1. This slurrywas then placed on a shaker for 10 minutes. The resulting slurry wasthen coated on the above interface with a Bird applicator, wet thickness0.5 mils. This layer was then dried at 135° C. for 6 minutes in a forcedair oven, resulting in a dry thickness of 2.0 microns.

A photoconductive layer containing 30 percent by volume hydroxysquarylium was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams Formvar 12/85, commerciallyavailable from Monsanto and 16 milliliters tetrahydrofuran. Added tothis solution was 0.36 grams of hydroxy squarylium and 100 grams 1/8"stainless steel shot. The above mixture was placed on a ball mill for 24hours. To 5 grams of this slurry was added 10 milliliters of additionalsolvent. This slurry was then coated on the above photogenerator layerwith a Bird applicator, to a wet thickness of 0.5 mils. The resultingdevice was dried at 135° C. for 6 minutes in a forced air oven. The drythickness of the photoconductive layer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containg 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Theresulting solution was mixed in 15 percent by weight of methylenechloride. All of these components were placed into an amber bottle anddissolved. The mixture was coated to a dry 25 micron thickness layer ontop of the generator layers using a Bird applicator. During this coatingprocess the humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE XII

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent by weight of duPont 49,000adhesive, a polyester available from duPont, in methylene chloride and1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator. The wetthickness was 0.5 mil. This layer was then allowed to dry for one minuteat room temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of about 0.05 microns.

A photogenerator layer containing 30 percent by volume of trigonalselenium, 25 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine and 45volume percent of polyvinyl carbazole was prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole and 18milliliters, 1:1 volume ratio, tetrahydrofuran:toluene. There was thenadded to this solution 2.1 grams of trigonal selenium and 100 grams ofstainless steel shot, 1/8" in diameter. The above mixture was thenplaced on a ball mill for 72 to 96 hours. In a 1 oz. amber bottle wasadded 0.04 gramsN'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine and 6.4milliliters of tetrahydrofuran-toluene, volume ratio 1:1. Added to thissolution was 2 grams of the ball milled slurry. This slurry was thenplaced on a shaker for 10 minutes. The resulting slurry was then coatedon the above 49,000 adhesive layer with a Bird applicator, to a wetthickness 0.5 mils. This device was then allowed to air dry 1 to 5minutes to a a dry thickness for the photogenerator layer of 0.5microns. The resulting device was then dried at 135° C. for 6 minutes ina forced air oven.

A photoconductive layer containing 30 percent by volume of hydroxysquarylium was prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams Formvar 12/85, and 16milliliters tetrahydrofuran. Added to this solution was 0.36 grams ofhydroxy squarylium and 100 grams 1/8" stainless steel shot. The abovemixture was placed on a ball mill for 24 hours. To 5 grams of thisslurry was added 10 milliliters of additional solvent. This slurry wasthen coated on the above generator layer with a Bird applicator, to awet thickness of 0.5 mils. The resulting device was dried at 135° C. for6 minutes in a forced air oven. The dry thickness of the photoconductivelayer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containg 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Theresulting solution was mixed in 15 percent by weight of methylenechloride. All of these components were then placed into an amber bottleand dissolved. The mixture was coated to a dry 25 micron thickness layeron top of the generator layers using a Bird applicator. During thiscoating process the humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE XIII

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent by weight of duPont 49,000adhesive, a polyester available from duPont, in methylene chloride and1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator. The wetthickness was 0.5 mil. This layer was then allowed to dry for one minuteat room temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of about 0.05 microns.

A photogenerator layer containing 33 percent by volume of trigonalselenium, and 13 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine in thephenoxy binder Bakelite available from Union Carbide was prepared asfollows:

In a 4 oz. amber bottle was added 1.6 grams of the above phenoxy resin,21 milliliters methyl ethyl ketone and 7 milliliters methoxy ethylacetate. Added to this solution was 3.2 grams of trigonal selenium, and200 grams 1/8" stainless steel shot. The above mixture was placed on aball mill for 72-96 hours. This slurry was then coated on the abovepolyester with a Bird applicator, to a wet thickness of 0.5 mils. Thislayer was allowed to air dry 2-5 minutes. The dry thickness was 0.5microns. This layer was then dried at 135° C. in forced air for 6minutes.

A photoconductive layer containing 30 percent by volume of hydroxysquarylium, was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams Monsanto Formvar 12/85, and16 ml. of tetrahydrofuran. Added to this solution was 0.36 grams ofhydroxy squarylium and 100 grams 1/8" stainless steel shot. The abovemixture was placed on a ball mill for 24 hours. To 5 grams of thisslurry was added 10 milliliters of additional solvent. This slurry wasthen coated on the above photogenerator with a Bird applicator, to a wetthickness of 0.5 mils. The resulting device was dried at 135° C. for 6minutes in a forced air oven. The dry thickness of the photoconductivelayer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE XIV

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 weight percent of duPont 49,000adhesive, in methylene chloride and 1,1,2-trichloroethane (4:1 volumeratio) with a Bird applicator. This layer was then allowed to dry forone minute at room temperature and 10 minutes at 100° C. in a forced airoven. The resulting layer had a dry thickness of 0.05 microns.

There was then overcoated on the above adhesive layer by known vacuumevaporation processes, a layer of arsenic triselenide, 0.5 microns inthickness.

A photoconductive layer containing 30 percent by volume vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000 polyesterin 16 milliliters methylene chloride. Added to this solution was 0.36grams of vanadyl phthalocyanine, and 100 grams 1/8" stainless steelshot. The above mixture was placed on a ball mill for 24 hours. To 5grams of this slurry was added 10 milliliters of methylene chloride.This slurry was coated on the above photogenerator layer with a Birdapplicator, to a wet thickness of 0.5 mils. The resulting layer wasallowed to air dry for 5 minutes. This device was dried at 135° C. for 6minutes in aa forced air oven. The dry thickness of the photoconductivelayer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Theresulting solution was mixed in 15 percent by weight of methylenechloride. All of these components were then placed into an amber bottleand dissolved. The mixture was coated to a dry 25 micron thickness layeron top of the generator layers using a Bird applicator. During thiscoating process the humidity was equal to or less than 15 percent.

The resulting device was annealed at 135° C. in a forced air oven for 6minutes.

EXAMPLE XV

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent weight of duPont 49,000polyester adhesive, in methylene chloride and 1,1,2-trichloroethane (4:1volume ratio) with a Bird Applicator. The layer was allowed to dry forone minute at room temperature and 10 minutes at 100° C. in a forced airoven. The resulting layer had a dry thickness was 0.5 microns.

There was then overcoated on the adhesive layer 49,000 by known vacuumevaporation processes, a layer of arsenic triselenide, 0.5 microns inthickness.

A photoconductive layer containing 30 percent by volume of hydroxysquarylium was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams Formvar 12/85, and 16milliliters of tetrahydrofuran. Added to this solution was 0.36 grams ofhydroxy squarylium, and 100 grams 1/8" stainless steel shot. The abovemixture was placed on a ball mill for 24 hours. To 5 grams of thisslurry was added 10 milliliters of additional tetrahydrofuran. Theresulting slurry was then coated on the above photogenerator layer witha Bird applicator, to a wet thickness of 0.5 mils. The resulting layerwas allowed to air dry for 5 minutes. This device was dried at 135° C.for 6 minutes in a forced air oven. The dry thickness of thephotoconductive layer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE XVI

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent weight of duPont 49,000adhesive, in methylene chloride and 1,1,2-trichloroethane 4:1 volumewith a Bird Applicator. The layer was allowed to dry for one minute atroom temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of 0.05 microns.

A photoconductive layer containing 30 percent by volume of vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000 polyesterin 16 milliliters methylene chloride. Added to this solution was 0.36grams of vanadyl phthalocyanine, and 100 grams 1/8" stainless steelshot. The above mixture was placed on a ball mill for 24 hours. To 5grams of this slurry was added 10 milliliters of methylene chloride.This slurry was coated on the above polyester with a Bird applicator, toa wet thickness of 0.5 mils. This layer was allowed to air dry for 5minutes. The resulting device was dried at 135° C. for 6 minutes in aforced air oven. The dry thickness of the photoconductive layer was 0.5microns.

A photogenerator layer containing 10 volume percent of trigonalselenium, 25 percent by volumeN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine and 55volume percent of polyvinyl carbazole was then prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole and 14milliliters 1:1 by volume tetrahydrofuran/toluene. Added to thissolution was 0.8 grams of trigonal selenium and 100 grams of 1/8"stainless steel shot. The above mixture was placed on a ball mill for72-96 hours. Five grams of this slurry was added to a solution of 0.18grams of polyvinyl carbazole and 0.15 gramsN,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine in 6.3 milliliters oftetrahydrofuran/toluene. The resulting solution was placed on a shakerfor 10 minutes. The slurry formed was then coated on the abovephotoconductive layer with a Bird applicator, in a wet thickness of 0.5mils. The resulting device layer was dried at 135° C. for 6 minutes in aforced air oven. The dry thickness of the photoconductive layer was 2.0microns.

The photogenerating layer was then overcoated with a charge transportlayer which was prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weight ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was thenannealed at 135° C. in a forced air oven for 6 minutes.

EXAMPLE XVII

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils a layer of 0.5 percent weight of duPont 49,000polyester adhesive, in methylene chloride and 1,1,2-trichloroethane (4:1volume ratio) with a Bird Applicator. The layer was allowed to dry forone minute at room temperature, and 10 minutes at 100° C. in a forcedair oven. The dry thickness was about 0.05 microns.

A photoconductive layer containing 30 percent by volume of vanadylphthalocyanine was then prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams of duPont 49,000, and 16-mlof methylene chloride. Added to this solution was 0.36 grams of vanadylphthalocyanine and 100 grams 1/8" stainless steel shot. The abovemixture was placed on a ball mill for 24 hours. To 5 grams of the slurrywas added 10 milliliters of methylene chloride. This slurry was coatedon the above adhesive interface with a Bird applicator to a wetthickness of 0.5 mils. This layer was allowed to air dry for 5 minutes.The resulting device was dried at 135° C. for 6 minutes in a forced airoven. The dry thickness of the photoconductive layer was 0.5 microns.

A photogenerator layer containing 33 percent by volume of trigonalselenium and 13 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine in aphenoxy resinous binder 54 percent by volume, was then prepared asfollows:

In a 4 oz. amber bottle was added 1.6 grams of the above phenoxy resin,21 milliliters methyl ethyl ketone and 7 milliliters methoxy ethylacetate. Added to this solution was 3.2 grams trigonal selenium, and 200grams 1/8" stainless steel shot. The above mixture was placed on a ballmill for 79-96 hours. This slurry was then coated on the abovephotoconductive layer with a Bird applicator, to a wet thickness of 0.5mils. The resulting device was allowed to air dry 2.5 minutes. The drythickness of the photoconductive layer was 0.5 microns. The device layerwas then dried at 135° C. in forced air for 6 minutes.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE XVIII

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent by weight of duPont 49,000adhesive, a polyester available from duPont, in methylene chloride and1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator. The wetthickness was 0.5 mil. This layer was then allowed to dry for one minuteat room temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of about 0.05 microns.

A photoconductive layer containing 30 percent by volume of hydroxysquarylium was prepared as follows:

In a 2 oz. amber bottle is added 0.76 grams Formvar 12/85, (Monsanto)and 16 milliliters tetrahydrofuran. Added to this solution was 0.36grams of hydroxy squarylium and 100 grams 1/8" stainless steel shot. Theabove mixture was placed on a ball mill for 24 hours. To 5 grams of thisslurry was added 10 milliliters of additional solvent. This slurry wasthen coated on the above adhesive interface with a Bird applicator, to awet thickness of 0.5 mils. The resulting device was dried at 135° C. for6 minutes in a forced air oven. The dry thickness of the photoconductivelayer was 0.5 microns.

A generator layer containing 10 percent by volume of trigonal selenium,and 25 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine and 65volume percent of polyvinyl carbazole was prepared as follows:

In a 2 oz. amber bottle was added 0.8 grams polyvinyl carbazole and14-milliliters 1:1 volume ratio, tetrahydrofuran:toluene. There was thenadded to this solution 0.8 grams of trigonal selenium and 100 grams ofstainless steel shot, 1/8" in diameter. The above mixture was thenplaced on a ball mill for 72 to 96 hours. In a 1 oz. amber bottle wasadded 0.15 gramsN'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. 0.18grams polyvinylcarbazole, and 6.3 milliliters oftetrahydrofuran-toluene, volume ratio 1:1. Added to this solution was 5grams of the ball milled slurry. The slurry formed was then placed on ashaker for 10 minutes. The resulting slurry was then coated on the abovephotoconductive layer with a Bird applicator, to a wet thickness 0.5mils. This layer was then dried at 135° C. for 6 minutes in a forced airoven, resulting in a dry thickness for the generator layer of 2.0microns.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer, A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

EXAMPLE XIX

A photoreceptive device was prepared by providing an aluminized Mylarsubstrate in a thickness of 3 mils, and applying thereto in a wetthickness of 0.5 mils, a layer of 0.5 percent by weight of duPont 49,000adhesive, a polyester available from duPont, in methylene chloride and1,1,2-trichloroethane (4:1 volume ratio) with a Bird applicator. The wetthickness was 0.5 mil. This layer was then allowed to dry for one minuteat room temperature and 10 minutes at 100° C. in a forced air oven. Theresulting layer had a dry thickness of about 0.05 microns.

A photoconductive layer containing 30 percent by volume of hydroxysquarylium was prepared as follows:

In a 2 oz. amber bottle was added 0.76 grams Monsanto Formvar 12/85 and16 ml tetrahydrofuran. Added to this solution was 0.36 grams of hydroxysquarylium and 100 grams 1/8" stainless steel shot. The above mixturewas placed on a ball mill for 24 hours. To 5 grams of this slurry wasadded 10 milliliters of additional solvent. The slurry formed was thencoated on the above adhesive layer with a Bird applicator, to a wetthickness of 0.5 mils. The resulting device was dried at 135° C. for 6minutes in a forced air oven. The dry thickness of the photoconductivelayer was 0.5 microns.

A photoconductive layer containing 33 percent by volume of trigonalselenium, and 13 percent by volume ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine in aBakelite phenoxy binder was prepared as follows:

In a 4 oz. amber bottle was added 1.6 grams of the above phenoxy resin,21 milliliters methyl ethyl ketone and 7 milliliters methoxy ethylacetate. Added to this solution was 3.2 grams trigonal selenium, and 200grams 1/8" stainless steel shot. The above mixture was placed on a ballmill for 72-96 hours. The resulting slurry was then coated on the abovephotoconductive layer with a Bird applicator, to a wet thickness of 0.5mils. The resulting device was allowed to air dry 2.5 minutes, followedby drying at 135° C. in forced air for 6 minutes. The dry thickness ofthe photoconductive layer was 0.5 microns.

The above photoconductive layer was overcoated with a charge transportlayer which was then prepared as follows:

A transport layer containing 50 percent by weight Makrolon®, apolycarbonate resin having a molecular weight (M_(w)) of from about50,000 to about 100,000 available from Larbensabricken Bayer A. G., wasmixed with 50 percent by weightN,N'-diphenyl-N,N'-bis(3-methylphenyl)1,1'-biphenyl-4,4'-diamine. Thissolution was mixed in 15 percent by weight of methylene chloride. All ofthese components were placed into an amber bottle and dissolved. Themixture was coated to a dry 25 micron thickness layer on top of thegenerator layers using a Bird applicator. During this coating processthe humidity was equal to or less than 15 percent.

The resulting device containing all of the above layers was annealed at135° C. in a forced air oven for 6 minutes.

Numerous other photoresponsive devices were prepared by repeating theprocedures of the above examples with the exception that there wasselected as the photogenerating layer a selenium tellurium alloy,containing 75 percent by weight of selenium, and 25 percent by weight oftellurium, or an arsenic selenium alloy, containing 99.99 percent byweight of selenium, and 0.1 percent by weight of arsenic.

Each of the above prepared devices were then tested for photosensitivityin the visible and infra-red region of the spectrum by negativelycharging the devices with corona to a -800 volts, followed bysimultaneously exposing each device to monochromatic light in awavelength range of from about 400 to about 1,000 nanometers. Thesurface potential of each device was then measured with an electricalprobe after exposure to given wavelengths. The percent discharge of eachdevice was then calculated as disclosed hereinbefore, which percentdischarge indicates photoresponse.

The photoresponse devices of Examples III, IV and V, responded to lightonly in the wavelength of about 400 to 675 nanometers, indicatingvisible photosensitivity, while the photoresponsive devices of ExamplesVI and VII, responded to light in the wavelength of about 580 to 950nanometers, with poor response in the blue and green wavelength range ofthe spectrum.

The devices as prepared in Examples VIII to XIX, had excellent responsein the wavelength range of from about 400 to about 950 nanometers,indicating both visible and infra-red photosensitivity for thesedevices.

Although the invention has been described with reference to specificpreferred embodiments, it is not intended to be limited thereto, ratherthose skilled in the art will recognize variations and modifications maybe made therein which are within the spirit of the invention and withinthe scope of the following claims.

I claim:
 1. An improved photoresponsive device comprised of a substrate,a hole blocking layer, an optional adhesive layer, an inorganicphotogenerating layer, an organic photoconductive layer sensitive toinfra-red radiation, and a top coating of a hole transport layer.
 2. Animproved photoresponsive device in accordance with claim 1 comprised inthe order stated of the following layers: (1) a substrate, (2) a metaloxide hole blocking layer, (3) an adhesive layer, (4) an inorganicphotogenerating layer, (5) a photoconductive composition capable ofenhancing or reducing the intrinsic properties of the photogeneratinglayer in the infra-red and/or visible region of the spectrum, whichcomposition is selected from the group consisting of organicphotoconductive compositions, charge transfer complex compositions,sensitizers, or mixtures thereof, and (6) a hole transport layer.
 3. Animproved photoresponsive device in accordance with claim 1 comprised inthe order stated of the following layers: (1) a substrate, (2) metaloxide hole blocking layer, (3) an adhesive layer, (4) a photoconductivecomposition capable of enhancing or reducing the intrinsic properties ofa photogenerating layer in the infra-red and/or visible region of thespectrum, which composition is selected from the group consisting oforganic photoconductive compositions, charge transfer complexcompositions, sensitizers, and mixtures thereof, (5) an inorganicphotogenerating layer and, (6) a hole transport layer.
 4. An improvedphotoresponsive device in accordance with claims 2 or 3 wherein thesubstrate is conductive, the metallic oxide is aluminum oxide, and theadhesive layer is comprised of a polyester resin.
 5. An improvedphotoresponsive device in accordance with claims 2 or 3 wherein thephotoconductive layer is comprised of an infra-red photoconductivematerial.
 6. An improved photoresponsive device in accordance withclaims 2 or 3 wherein the photoconductive material is a phthalocyaninepigment.
 7. An improved photoresponsive device in accordance with claim6 wherein the photoconductive material is vanadyl phthalocyanine.
 8. Animproved photoresponsive device in accordance with claim 6 wherein thephotoconductive material is a metal free phthalocyanine.
 9. An improvedphotoresponsive device in accordance with claim 6 wherein thephotoconductive material is chloroaluminum phthalocyanine chloride. 10.An improved photoresponsive device in accordance with claim 6 whereinthe photoconductive material is chlorogallium phthalocyanine chloride.11. An improved photoresponsive device in accordance with claims 2 or 3wherein the photoconductive material is a squarylium composition of theformula: ##STR3## wherein R is hydrogen, an alkyl group, or a hydroxy(OH) group.
 12. An improved photoresponsive device in accordance withclaim 11 wherein the squarylium composition is a hydroxy squarylium or amethyl squarylium.
 13. An improved photoresponsive device in accordancewith claims 2 or 3 wherein the sensitizer is derived from the class ofcyanine dye sensitizers, which cause sensitization in the infraredregion.
 14. An improved photoresponsive device in accordance with claims2 or 3 wherein the photogenerating layer is comprised of selenium, ahalogen doped selenium substance, selenium alloys, or halogen dopedselenium alloys.
 15. An improved photoresponsive device in accordancewith claim 14 wherein the selenium alloys are comprised of seleniumarsenic, and selenium tellurium.
 16. An improved photoresponsive devicein accordance with claim 15 wherein the selenium alloys are doped withchlorine in an amount of from about 50 parts per million to about 200parts per million.
 17. An improved photoresponsive device in accordancewith claims 2 or 3 wherein the photogenerating layer is trigonalselenium.
 18. An improved photoresponsive device in accordance withclaims 2 or 3 wherein the photogenerating layer is trigonal seleniumdoped with sodium carbonate, and sodium selenite.
 19. An improvedphotoresponsive device in accordance with claims 2 or 3 wherein thethickness of the adhesive layer is from about 0.01 to about 0.3 microns,the thickness of the photogenerating layer is from about 0.1 microns toabout 10 microns, when the photogenerating layer contains from about 5percent to about 100 percent by volume of photogenerating pigment, andthe thickness of the photoconductive layer is from about 0.1 microns toabout 10 microns, when the photoconductive composition contains fromabout 5 percent to about 100 percent by volume of photoconductivepigment.
 20. An improved photoresponsive device in accordance withclaims 2 or 3 wherein the photogenerating layer is comprised of aninorganic photoconductive composition dispersed in a resinous binder,and the photoconductive layer is comprised of an organic photoconductivecomposition dispersed in a resinous binder.
 21. An improvedphotoresponsive device in accordance with claim 20 wherein the resinousbinder for the photogenerating layer is a poly(hydroxyether).
 22. Animproved photoresponsive device in accordance with claim 20 wherein theresinous binder for the photogenerating layer is a polyvinylcarbazole.23. An improved photoresponsive device in accordance with claim 20wherein the binder for the photoconductive layer is a polycarbonate. 24.An improved photoresponsive device in accordance with claim 19 whereinthe binder for the photoconductive layer is a polyester.
 25. An improvedphotoresponsive device in accordance with claim 19 wherein the binderfor the photoconductive layer is polyvinylcarbazole.
 26. An improvedphotoresponsive device in accordance with claims 2 or 3 wherein thecharge transport layer comprises molecules of the formula: ##STR4##dispersed in a highly insulating and transparent organic resinousmaterial wherein X is selected from the group consisting of (ortho) CH₃,(meta)CH₃, (para)CH₃, (ortho)Cl, (meta)Cl, (para)Cl.
 27. An improvedphotoresponsive device in accordance with claim 26 wherein the transportlayer is comprised ofN,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1,1-biphenyl]-4,4'-diamine. 28.An improved photoresponsive device in accordance with claim 19 whereinthe resinous binder is a polycarbonate having a molecular weight of fromabout 20,000 to about 100,000.
 29. An improved photoresponsive device inaccordance with claim 26 wherein the resinous binder contains from about10 percent by weight to about 75 percent by weight of the diaminecompound, and the thickness of the charge transport layer is from about5 microns to about 50 microns.
 30. An improved photoresponsive device inaccordance with claims 2 or 3 wherein the substrate is comprised ofindium tin oxide.